Living near a high traffic road may give you dementia

People who live near major roads have higher rates of dementia, research published in the Lancet suggests.

At least 10% and possibly more of dementia cases among people living within 50 meters of a major road could be caused by the mixed bag of pollutions that traffic causes.
The researchers, who followed nearly 2 million people in Canada over 11 years, say air pollution and  noise of traffic could be contributing to the brain's decline.
Dementia experts  around the world said the findings were "certainly plausible".
Nearly 50 million people around the world have dementia.

However, the causes of the disease, that robs people of their memories and brain function76, have not been understood before now. With this new research, scientists are beginning to look into other environmental causes for the disease. For example, chemicals in water and food, insecticides and fungicides; all things that find their way into our bodies and do not come from natural sources.

Population growth

The study in the Lancet followed nearly two million people in the Canadian province of Ontario, between 2001 and 2012.
There were 243,611 cases of dementia diagnosed during that time, but the risk was greatest in those living closest to major roads.
Compared with those living 300m away from a major road the risk was:

• 7% higher within 50m
• 4% higher between 50-100m
• 2% higher between 101-200m

The analysis suggests 7-11% of dementia cases within 50m of a major road could be caused by traffic. And that is a conservative estimate.
Dr Hong Chen, from Public Health Ontario and one of the report authors, said: "Increasing population growth and urbanization have placed many people close to heavy traffic, and with widespread exposure to traffic and growing rates of dementia, even a modest effect from near-road exposure could pose a large public health burden.
"More research to understand this link is urgently needed, particularly into the effects of different aspects of traffic, such as air pollutants and noise."
The researchers suggest noise, ultrafine particles of carbon, nitrogen oxides and particles from tyre-wear may be involved.

'Provocative'

"This is an important paper," says Prof Martin Rossor, the UK's National Institute for Health Research director for dementia research.
He added: "This is a disorder with a high population prevalence so such effects can have important public health implications."
Prof Tom Dening, the director of the Centre for Dementia said: "It is certainly plausible that air pollution from motor exhaust fumes may contribute to brain pathology that over time may increase the risk of dementia, and this evidence will add to the unease of people who live in areas of high traffic concentration.
"Undoubtedly living in conditions of severe air pollution can't be good for anyone."


The best advice to reduce the risk of dementia is to do the things that we know are healthy for the rest of the body - stop smoking, exercise and eat healthy organic foods.
And if it is possible for you ... Don't live near major traffic roads.